Quick Takes

3-D Printer Makes Liquid Metal Wires

Flexible LED displays are now in your future thanks to technology developed at NC State. A team of researchers demonstrated a remarkable process for creating liquid metal wires on a 3-D printer in July. These wires could be used to create any number of stretchable electronics, including ultra-flexible monitors.

Liquid metal technology from NC State could make future LED displays flexible.

How do you create a wire out of liquid metal? Easy, says Michael Dickey, a chemical and biomolecular engineer. “We’ve found that a liquid metal alloy of gallium and indium reacts to the oxygen in the air at room temperature to form a ‘skin’ that allows the liquid metal structures to retain their shapes.”

Collin Ladd, a 2013 graduate, was key to this project, Dickey adds. “He helped develop the concept, and literally created some of this technology out of spare parts he found himself.”

Electrical and computer engineering professor John Muth and Ph.D. student Ju-Hee So also worked on the process, published online in Advanced Materials.

Helping Students Gain Environmental Literacy

Environmental education programs that take middle-schoolers outdoors help minority students close a gap in environmental literacy, according to research from NC State.

Published in PLOS ONE, the study showed that time outdoors seemed to affect African-American and Hispanic students more than Caucasian students, improving minority students’ ecological knowledge and cognitive skills. Researchers tested the environmental literacy of sixth- and eighth-grade students in 18 N.C. schools. Half of the schools studied had registered an environmental education program with the state.

Students learn more when their science lessons take them outside, NC State researchers say.

“This is one of the first studies on a broad scale to focus on environmental literacy, which is more than mastering facts,” says co-author Nils Peterson of NC State’s College of Natural Resources.

Sixth graders showed greater gains in environmental literacy than eighth graders, suggesting that early middle school is the best window for environmental literacy efforts, notes graduate student Kathryn Stevenson. North Carolina Sea Grant funded the study.

Game Tech to Steer Roaches

Roaches could soon be saving lives. NC State researchers are using video game technology to remotely control cockroaches. Ultimately, the technology could allow the insects to explore collapsed buildings.

Incorporating Microsoft’s motion-sensing Kinect system into an electronic interface developed at NC State, the team tracks how large roaches respond to the remote control. The insects might even be fitted with mikes and sensors to detect survivors trapped in debris. “We want to build on this program, incorporating mapping and radio frequency techniques that will allow us to use a small group of cockroaches to explore and map disaster sites,” says Alper Bozkurt, an electrical and computer engineer with funding from the National Science Foundation.

Technology from the Kinect gaming system could help steer cockroaches through damaged buildings.

The interface controlling the roach is wired to the antennae and and cerci, or rear spine. The wires attached to the cerci spur the roach into motion and those attached to the antennae send small charges that trick the roach into thinking that it is approaching a barrier steering them in another direction.

Multitude of Mates Benefit Honey Bees

When it comes to honey bees, having more mates is better. A new study from NC State, the University of Maryland and the U.S. Department of Agriculture shows that genetic diversity is key to honey bee survival.

Researchers found that colonies where the queen had mated at least seven times were 2.86 times more likely to survive the 10-month working season. Specifically, 48 percent of colonies with queens who had mated at least seven times were still alive at season’s end. Only 17 percent of the less genetically diverse colonies survived.

“Forty-eight percent survival is still an alarmingly low survival rate, but it’s far better than 17 percent,” says entomologist David Tarpy. Now beekeepers can consider breeding strategies to help colonies survive, he adds.

The research was published online in the journal Naturwissenschaften. The work was supported by the USDA Cooperative State Research, Education and Extension Service, the USDA Agricultural Research Service, the N.C. Department of Agriculture and Consumer Services and the National Honey Board.

Older is Wiser

There’s a perception in some tech circles that older programmers can’t keep pace with rapidly changing technology. Actually, the opposite is true. NC State researchers report that knowledge and skills of programmers actually improve over time.

“We found that, in some cases, veteran programmers even have a slight edge,” says computer scientist Emerson Murphy-Hill. His team compiled data on more than 80,000 programmers via a social networking site. The researchers compared users’ ages with reputation scores, then tracked topics users discussed. The team also examined how knowledgeable older users were about new technologies.

The findings are good news for seasoned programmers. Older users scored higher in reputation, were familiar with a wider range of subjects and were more up-to-date than younger users. Ph.D. student Patrick Morrison presented a paper on the findings.

Smart System for Insulin Delivery

A new drug delivery technique developed at NC State and UNC-Chapel Hill could improve diabetes management and ultimately aid in the treatment of cancer. The innovative process involves a sponge-like material that is injected into a patient’s bloodstream. The material, a matrix containing nanocapsules made from a porous polymer, releases insulin when it senses a rise in blood sugar.

Researcher Zhen Gu, of the joint biomedical engineering program, says the smart drug delivery system mimics the function of healthy cells that produce insulin. In lab tests using mice, researchers found the sponge matrix was effective at managing blood sugar for up to 48 hours.

The research team includes colleagues at the Koch Institute for Integrative Cancer Research at MIT and the Department of Anesthesiology at Boston Children’s Hospital. Published online in ACS Nano, the research was supported by the Leona M. and Harry B. Helmsley Charitable Trust Foundation, and the Tayebati Family Foundation.

Mental Health Treatment Pays Off

Investing in outpatient mental health treatment is a bargain for society, NC State researchers report. Conducted in collaboration with RTI International and the University of South Florida, the research shows that outpatient treatment significantly reduces arrest rates for people with mental health problems and saves taxpayers money.

“This study shows that providing mental health care is not only in the best interest of people with mental illness, but in the best interests of society,” says Sarah Desmarais, a psychology faculty member at NC State.

Researchers identified 4,056 people who had been hospitalized for mental illness in 2004 or 2005 and then tracked them from 2005 to 2012. They determined which individuals were receiving government-subsidized medication and which were receiving government-subsidized outpatient services, such as therapy. The researchers also determined who was arrested during the seven-year period.

The team then compared criminal justice costs with mental health treatment costs. Individuals who were arrested received less treatment, and each cost the government approximately $95,000 during the study period. Individuals who were not arrested received more treatment, and cost the government approximately $68,000. “It costs about $10 less per day to provide treatment and prevent crime. That’s a good investment,” Desmarais says.

The findings were published in the journal Psychiatric Services. Lead author is Richard Van Dorn of RTI. The Florida Agency for Health Care Administration supported the research.

“We believe this partnership drives commercial value for our research in a manner not previously explored, at a time when wireless technology is at the center of many existing and new fields,” says Dinesh Divakaran, licensing associate at NC State.

WRCNC has industry experts as well as sophisticated test chambers and equipment that will accelerate development and commercialization of many NC State projects. The center began as an economic development initiative by the Town of Wake Forest and the GoldenLEAF Foundation. WRCNC also conducts product and regulatory studies, research, regulation mapping and planning, and intellectual property expansion.

Better Understanding of Facebook Behavior

Employers are increasingly using Facebook to screen job applicants and weed out candidates they think have undesirable traits. But a new study from NC State shows that those companies may have a fundamental misunderstanding of online behavior and, as a result, may be eliminating desirable job candidates.

Researchers tested 175 study participants to measure the personality traits that companies look for in job candidates, including conscientiousness, agreeableness and extroversion. The participants were then surveyed on their Facebook behavior, allowing researchers to see which Facebook behaviors were linked to specific personality traits.

The results likely surprise many corporate human resource professionals. “Companies often scan a job applicant’s Facebook profile to see whether there is evidence of drug or alcohol use, believing that such behavior means the applicant is not conscientious or responsible and self-disciplined,” says psychology professor Lori Foster Thompson.

But there’s no significant correlation between conscientiousness and an individual’s willingness to post content on Facebook about alcohol or drug use, she says. Companies that are looking for extroverts — such as those hiring in sales or marketing — may be doing themselves a great disservice. The findings were published online in Cyberpsychology, Behavior and Social Networking. Co-authors were faculty member Adam Meade and doctoral student Will Stoughton.

Life is Possible; Barely

Life as we know it is based upon the elements of carbon and oxygen. Now a team of physicists, including one from NC State, is looking at the conditions necessary to the formation of those two elements in the universe. They’ve found that when it comes to supporting life, the universe leaves very little margin for error.

Carbon and oxygen are produced when helium burns inside of giant red stars. The key to carbon formation is an excited state of carbon-12 known as the Hoyle state. Oxygen is produced by the combination of another alpha particle and carbon.

NC State physicist Dean Lee and German colleagues had previously confirmed the existence and structure of the Hoyle state with a numerical lattice that allowed the researchers to simulate how protons and neutrons interact. These protons and neutrons are made up of elementary particles called quarks. The light quark mass is one of the fundamental parameters of nature, and this mass affects particles’ energies.

In new lattice calculations done at the Juelich Supercomputer Centre, the physicists found that just a slight variation in the light quark mass will change the energy of the Hoyle state, and this in turn would affect the production of carbon and oxygen in such a way that life as we know it wouldn’t exist.

Published in Physical Review Letters, the work was supported by the U.S. Department of Energy, the European Union HadronPhysics3 Project, the European Research Council and several German funding agencies.

Look and Learn

By tracking facial expressions, researchers at NC State assess the emotions of students engaged in interactive online learning — and predict the effectiveness of online tutoring sessions.

The research is part of larger efforts to develop artificial intelligence software, says computer scientist Kristy Boyer. “The program, JavaTutor, will not only respond to what a student knows, but to each student’s feelings of frustration or engagement. This is important because research shows that student emotion plays an important role in the learning process.”

Researchers used the automated Computer Expression Recognition Toolbox, or CERT, to evaluate the facial expressions of 65 college students engaged in one-on-one online tutoring sessions. CERT was able to identify facial movements associated with learning-centered emotions, such as frustration or concentration. The automated program’s findings were consistent with expert human assessments more than 85 percent of the time. The researchers used observational data from CERT along with student self-assessments and test results to develop models that could predict how effective a tutorial session was, based on facial expressions.

The team includes Ph.D. student Joseph Grafsgaard; undergraduate student Joseph Wiggins; Eric Wiebe, professor of science, technology, engineering and math education; and James Lester, professor of computer science. The National Science Foundation supported the research.

Cannibalistic Tadpoles Offer Evolution Insight

A carnivorous, cannibalistic tadpole may play a role in understanding the evolution and development of digestive organs and lead to better diagnosis and prevention of intestinal birth defects, according to new research at NC State.

Cannibalistic Tadpoles provide important data.

Developmental biologist Nanette Nascone-Yoder, graduate student Stephanie Bloom and postdoc Cris Ledon-Rettig looked at two frog species that differ in diet and last shared a common ancestor about 110 million years ago. One is an aggressive species of frog that is carnivorous — and cannibalistic — in the tadpole stage.

The team exposed frog embryos to molecules that changed their gut development, prompting the carnivore frogs’ systems to function more like their non-carnivore cousins and vice-versa.

“Understanding how and why the gut develops different shapes to adapt to different diets and environments during evolution gives us insight into what types of processes can be altered in the context of human birth defects, another scenario in which the gut also changes its shape and function,” Nascone-Yoder says.

The findings appear in Evolution and Development. James Hanken, Carlos Infante and Anne Everly from the Harvard Museum of Comparative Zoology contributed to the work. The research was funded in part by the National Science Foundation.